/Engine/Source/Runtime/Engine/Public/WorldPartition/ErrorHandling/WorldPartitionStreamingGenerationProxyErrorHandler.h
Called when a data layer instance does not have a data layer asset
virtual void OnInvalidReferenceDataLayerAsset ( const [UDataLayerInstanceWithAsset](API\Runtime\Engine\WorldPartition\DataLayer\UDataLayerInstanceWithAsset) * DataLayerInstance )